Releasing device for pipe wrenches



NfKrSMlTH. RELEASING DEVICE FOR PIPE wnswcnss.

Patentedsept. 5, 1922.

APPLICATION FILED SEPT- 30, 1921.

. I, I; 7 I I I Patented Sept. 5,, i922.

srrss PATENT oFFIcE.

NELSON K. SMITH, F DALLAS, TEXAS.

RELEASING DEVICE FOR PIPE WRENCHES.

I Application filed September 30, 1821 Serial No. 504,454

improvements in releasing devices forpipewrenches, and more particularly for that type of wrenches having a aw and a chain for gripping the cylindrical object to be operated.

the accompanying drawings. It is understood that during the operation of the wrench with a rotary rig, the teeth of the jaw become wedged into the surface of the work and the chain drawn so tightly around the same, that it is diflicult to release the wrench when the operation is completed.

The object of the invention is to provide means for releasing the chain, of such a wrench from the work in a simple and expeditious manner. A further object is to provide means attached to one end on the chain, whereby the chain may be snugly engaged around the work or released therefrom.

A construction designed to carry out the invention will be hereinafter described together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and reference to the accompanying drawings, in which an example of the invention is shown and wherein:

Fig. 1 is a plan view of a pipe wrench provided with a releasing device constructed in accordance with my invention, and

Fig. 2 is a detail of the same.

In the drawings the numeral 10 designates a handle lever of a pipe wrench provided with a releasing device embodying my invention. Attached to one end of the lever is a jaw 11 adapted to bite the surface of a cylindrical object A, and a chain 12 adapted to be engaged around the said object or work.

Provided at the free end of the said chain is a latch lever 13 which is pivoted between links 14 on a pin 15. The pivoted endof the lever is provided with 2. lug 16 arranged to engage a boss 17 on the handle lever 10,

so that when the lever 13 is swung inwardly An example of such a type is illustrated in into engagement with the lever 10, the links 14 will be drawn rearwardly and inwardly,

thereby drawing the chain 12 around the 1 object A.

The inner side of the lever 13 is provided wlth an elongated recess 18 from which a slot 19 extends, through the end of the lever;

A transverse aperture 20 extends through the lever 13 from the recess at the end op posite to the slot 19. An elongated spring 21 having a head 22 is passed through the said aperture and then bowed at substantially right angles so that the other end may be slidably engaged in the slot 19. This spring projects beyond the inner side of the lever 13.

pivoted on a pin 24. When the lever '13 is swung inwardly into engagement with the lever 10, the keeper is adapted to be swung forwardly over the end of the lever 13 to hold the same in position. When the lever 13 is in such position, the spring 21 is compressed, thereby holding the lever in frictional engagement in the keeper, which prevents the latter from releasing the lever during the operation of the wrench.

It is obvious that the lug 16 is off-center with relation to the pivots of the chain and the pull tends to swing the lever outwardly. By swinging the keeper backwardly the ten sion of the spring 21 is released, whereby the lever 13 is sprung outwardly, disengaging the lug 16, as is shown in dotted lines in Fig. 2. The spring action is however, only initial, as the pull of the chain accomplishes the outward swing of the lever. It will be readily seen that the tens on of the chain 12 is broken so that the latter may be easily removed from the work. 7

It is pointed out that a device constructed in accordance with my invention provides means for engaging the chain of a pipe wrench around the work as well as means for expeditiously releasing the chain there from.

Various changes and modifications may be made without departing from the spirit of the invention.

What I claim, is: y

1. The combination with the handle lever, jaw, and chain of a pipe wrench, of a release lever pivotally connected with the end of the chain and free from the handle lever, a lug on the pivoted end of the re lease lever adapted to engage the handle lever and "fulcrum thereon for drawing the chain taut about an article, and a keeper pivoted on the handle lever and snugly engaging on the outer end 01 the release lever.

52. The combination with the handle lever, jaw, and chain ot a pipe wrench, oi a releasing device comprising a lever pivoted at the end of the chain and provided with a lug adapted to engage the handle lever, the lever being adapted to be swung into engagement with the handle lever, and means for fastening the lever in position.

The combination with the handle lever, jaw, and chain of a pipe wrench, of a releasing device attached to the end of the chain, and adapted to engage a fulcrum point on the handle lever and to be swung into proximity to the same, the handle le' -ver being provided with a keeper for holding the device in position, and means mounted on the device for holding the same in frictional engagement with the keeper.

4. The combination with the handle lever, jaw, and chain of a pipe wrench, of a releasing device comprising a lever pivoted to the end of the chain, the handle lever having a boss adapted to be engaged by the pivoted end of the lever, the lever being adapted to be swung into engagement with the handle lever, and means tor fastening the lever in position.

5. The combination with the handle lever, jaw, and chain ot' a pipe wrench, of a release lever pivotally connected with the end of the chain and free from the handle lever, a lug on the pivoted end of the release lever adapted to engage the handle lever and tulcrum thereon for drawing the chain taut about an article, a keeper pivoted on the handle lever and snugly engaging on the outer end of the release lever, and resilient means for holding the outer end of the re lease lever in snug engagement with the keeper and also for imparting an initial swing to the said lever when the keeper is swung therefrom.

6. The combination with the handle lever, jaw, and chain of a pipe wrench, of a release lever pivoted at the end of the chain and adapted to engage the handle lever at a point out of alignment with pivots of the chain whereby the pull of the chain tends to swing the lever outwardly, and means for fastening the lever in position, the lever having a spring for imparting initial swing when the lever is released.

In testimony whereof I aflii: my signature.

NELSON K. SMITIL 

